<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    /* 
    sdsdsd
    sdsdsd
    */
    h1,
    p {
      /* color: red; */
      font-size: 40px;
    }
  </style>
</head>

<body>
  <h1>页内 CSS</h1>
  <p>this is content</p>
  <p>this is content</p>
  <p>this is content</p>
  <p>this is content</p>
  <p>this is content</p>
</body>

</html>